1. Field of the Invention
The present invention relates to a ground fault monitor module for a circuit breaker trip unit. More specifically, the present invention relates to a ground fault display and monitor module for trip unit which is coupleable to one of a plurality of different modules, where the trip unit is configured to automatically recognize the type of module to which it is coupled and apply signals to the module which are compatible with the module.
2. Related Art
In general, display units for circuit breaker trip units are known. Referring to U.S. Pat. No. 4,870,531 issued to Robert J. Danek, there is shown a circuit interrupter having a display for viewing circuit interrupter settings. The display removably connects to the electronic trip unit of the interrupter, and displays interrupter values and settings when in operation. When the display unit is not in place, a security cover 20 may be positioned within a recess which is adapted to accept the display.
U.S. Pat. No. 4,751,605, issued to Mertz et al., also discloses a trip device for a circuit interrupter having a display unit. The display unit is portable and is coupleable to the trip device to display various circuit interrupter values. The display unit includes an alphanumeric display, a microprocessor, memory, and an apparatus associable with complementary apparatus in the trip device to transfer the contents of memory areas in the trip device to the memory of the display device. The content of the memory is selectively displayed by the reader.
While various display unit configurations are available for circuit interrupters (breakers), it would be useful and desirable to provide a trip unit useable with a plurality of different display units, where each display unit is configured to display a range of values for a given variable monitored by the trip unit e.g. current, temperature, energy, power, etc. Accordingly, depending upon the application for a circuit breaker, only a display unit configured to display the variables which are needed for the application is provided.